1. Field of the Invention
The present invention relates to a water-based particulate dispersion containing an oil-soluble dye, an ink for ink-jet recording containing the colored particulate dispersion, and an ink-jet recording method using the ink for ink-jet recording.
2. Description of the Related Art
In recent years, accompanying the more widespread use of computers, ink-jet printers have come to be widely used for printing on paper, film, cloth and the like, not only in offices but in homes as well. Oil-based inks, water-based inks, and solid inks are known as inks for ink-jet recording. Among these inks, water-based inks are advantageous from the standpoints of ease of manufacture, handling, odor, safety, and the like, and thus, water-based inks are mainly used.
However, most water-based inks use a water-soluble dye which dissolves in a molecular state. Thus, water-based inks have advantages that transparency and color density thereof are high. However, because these dyes are water-soluble, their water resistance is poor. When printing is carried out on so-called regular paper, problems arise in that bleeding occurs such that printing quality markedly deteriorates, and that light resistance is poor.
In order to overcome the above-described problems, Japanese Patent Application Laid-Open (JP-A) Nos. 56-157468, 4-18468, 10-110126, 10-195355 and the like, for example, have proposed water-based inks that utilize a pigment and a dispersed dye.
However, with these water-based inks, although the water resistance is improved to a certain extent, it is still insufficient. There are further problems, in that storage stability of a dispersion of the pigment and the dispersed dye in the water-based ink is lacking, it is easy for the ink to become clogged in ink discharge ports, and the like. Moreover, in the case of such water-based inks, generally, the hue is insufficient, and there are problems with color reproducibility due to insufficient color tone.
On the other hand, JP-A Nos. 58-45272, 6-340835, 7-268254, 7-268257, and 7-268260 propose methods of encapsulating dyes in urethane or polyester dispersion particles. Moreover, JP-A No. 11-269418 and U.S. Pat. No. 5,085,698 propose a method of using, as a dispersing agent, a block copolymer which is formed by a hydrophobic segment and a hydrophilic segment. However, with ink-jet inks obtained by these methods, there are problems in that the color tone is insufficient and the color reproducibility is also insufficient.
Further, JP-A Nos. 9-59552, 9-111163, 9-255887, 10-36728, 11-286637 and the like disclose that the color tone can be improved by using a dye in which an aromatic diamine is coupled to a color photographic coupler. However, in these inventions, there are problems in that there is a tendency for particle diameters or a particle diameter distribution of the dispersion to be large, dispersion stability and suitability for printing are insufficient, and the color tone varies in accordance with the type of image-receiving paper.